Court and Spark, released 41 years ago this week, found Joni Mitchell ascending to the top of the charts, even as she began adding bold new complexities to her music. Long a solo-performing folk artist, she discovered new vistas working in more collaborative, more improvisational settings. Thus began her so-called jazz period, as Robben Ford and a group of like-minded musicians from LA Express helped bring things out of Mitchell that few knew were even there.

“I couldn’t agree with you more,” Ford tells us, in an exclusive Something Else! Sitdown. “I thought she and John Guerin, the drummer with the LA Express, were going to get married at some point. They were very close, and I think he influenced her quite a bit from the jazz side of things. They lived together, so he was exposing her to Betty Carter and Billie Holiday and Miles Davis. I think it, indeed, opened her up musically in a way that wouldn’t have otherwise happened.”

As Court and Spark raced up the charts, Tom Scott led LA Express (which also included Ford, Guerin, Larry Nash and Max Bennett) into Joni Mitchell’s first tour with a live band. The 1974 concert disc Miles of Aisles — which saw Mitchell performing not just with her trusty acoustic but also at the piano — followed to No. 2 Billboard success. Ford then appeared on 1975’s Grammy-nominated The Hissing of Summer Lawns, while other members of LA Express sat in for Hejira in 1976 and Don Juan’s Reckless Daughter from the following year.

Along with 1979’s Mingus, the zenith of her intriguing jazz experimentalism, they remain some of Joni Mitchell’s most closely dissected (if not always best loved) albums. Sidemen like Robben Ford still marvel over the tidal changes she led her own career through, before retreating into more commercial waters by the 1980s.

“She was always a brilliant musician — and particularly when she sat down at the piano,” Ford adds. “Her music could become very expansive. With the guitar or on the dulcimer, she didn’t have a lot of technique on those instruments. But on the piano, she developed her own language. It became orchestral, like her mind. She had a big mind. So, I couldn’t agree with you more. It was an amazing period, certainly in her music — but it was an incredible legacy in music in general.”

Court and Spark, nominated for a album of the year Grammy, remains Joni Mitchell’s commercial peak — not just for this era, but for any. A No. 2, double-platinum smash, it was also home to one of Mitchell’s best-known singles: “Help Me” became her first (and, so far, lone) Top 10 hit, while earning another two Grammy nominations. Her next four albums went gold, but saw declining sales, despite the inclusion of the hit version of “Big Yellow Taxi” on Miles of Aisles, which just missed the Top 20.

Nick DeRiso has written for USA Today, American Songwriter, All About Jazz, and a host of others. Honored as columnist of the year five times by the Associated Press, Louisiana Press Association and Louisiana Sports Writers Association, he oversaw a daily section named Top 10 in the U.S. by the AP before co-founding Something Else! Nick is now associate editor of Ultimate Classic Rock.